Reply to Standard Mix Deck USB MIDI problems.

When I plug in my mix deck, and switch a deck to USB mode and my audio source to 'PC'. When I do this, I get an extremely loud ticking sound over whatever music I'm playing. Its SO loud, the music itself from Serato DJ Intro is almost inaudible. I was wondering what the problem is. I've tried uninstalling the drivers, and the software and then reinstalling them. I just can't figure it out.